the site, and Gilbert had hired Earr, Thaw & Fraser Co. to supply limestone for the mansion. In addition, A. J. Robinson & Co. had been hired as the building's general contractor, and Gilbert was responsible for interior finishes, including furniture. L. Alavoine & Co. and Messrs. William Baumgarten & Co. were awarded the contract for the house's interior decoration in May 1908. The house was completed in 1908 and used just of its Fifth Avenue frontage; the rest was used for a lawn. According to the 1910 United States census, Frieda and Felix Warburg lived in the house with their five children and 13 servants. The family hosted numerous events at their house. These included the wedding of their daughter Carola in 1916, which was attended by 900 guests; a "dramatic reading" to raise money for World War I relief in 1918; and a fundraiser for Jewish charities in 1928. Frieda took title to the house in January 1924. On October 20, 1937, Felix Warburg died of a heart attack within the Warburg House. In his will, Felix had bequeathed his ownership stake in the Warburg House to Frieda. She remained in the mansion with a son and relatives who had fled Nazi Germany in the 1930s. The house continued to host events such as a meeting of the National Council for Jewish Women in 1938. Rising property tax as a consequence of nearby development greatly strained the Warburgs' finances; by 1941, the city government had appraised the property as being worth $665,000, of which the land was worth $625,000 (). Frieda Warburg rented an apartment at 1070 Fifth Avenue in 1940. In May 1941, she sold the mansion to developer Henry Kaufman and architect Emery Roth, who intended to redevelop the site into an eighteen-story apartment building. The New York Herald Tribune reported that the house had been sold for less than $225,000. Roth submitted his plans for an apartment house to the New York City Department of Buildings (DOB) in July 1941; workers had started demolishing the Warburg residence. However, the developers' plans did not progress further, and the mansion reverted to Frieda. Jewish Museum of New York On January 14, 1944, Frieda Warburg donated the mansion to the Jewish Theological Seminary of America (JTS), commemorating what would have been Felix Warburg's 73rd birthday. She made the donation in memory of her husband, her father, and her